1. Field of the Invention
The invention pertains to improved electrooptical switches and more particularly relates to novel directionally coupling channel wave guide electrooptical switches employing electric field-effect liquid crystal compositions and compatible for use in large scale, integrated multiple switch matrix arrays.
2. Description of the Prior Art
Optical switching devices employing electrooptical materials such as LiNbO.sub.3 or LiTaO.sub.3 are well known in the art. While some degree of success has been achieved in devising such electric field switched devices in matrix forms, the use of these solid crystalline materials imposes certain serious limitations on the situation.
Generally, the size of available LiNbO.sub.3 or LiTaO.sub.3 crystals is limited to about one by three inches, and there is no apparent opportunity seen for overcoming this size limitation without extreme expense. No other solid electrooptic materials are known to have large electrooptic coefficients and otherwise suitable optical properties. With array substrate sizes so limited, the number of switches that may be employed in the matrix switches constructed of such materials is evidently severely limited.